Mineral oil compositions and processes of preparing the same



Patented Apr. 16, 1940 PATENT OFFICE MINERAL OIL COMPOSITIONS AND PROG-ESSES OF PREPARING THE SAME Anderson W. Balaton and Everett J. Hofiman,

Chicago, 111., assignors to Armour and Company, Chicago, 111., acorporation of Illinois No Drawing. Application October 14, 1938 SerialNo. 235,094

7 Claims.

This invention relates to mineral oil compositions and processes ofpreparing the same, and it comprises mineral oil compositions, such aslubricating oils and greases, containing small amounts of an acylatedand polymerized coumarone, it further comprises such mineral oilcom-positions containing small amounts of the product of acylatingcoumarone, or one of its polymers, in the presence of a metallicchloride 10 acylatin'g catalyst, hydrolyzing the intermediate metallicchloride complex and recovering the catalyst-free acylated andpolymerized coumarone.

For many uses in the art lubricating oil com- 16 positions having lowpour points must be used.

The pour point of an oil is in part directly related.

to the amount of parafiin wax in the oil and it is customary to dewaxthe oil both for the recovery of usable pa'raflin and for lowering the20 pour points of the oil. Even after drastic dewaxing operations thefinal lubricating oil does not always have as low a pour point as theart desires. Paraffin wax itself, however, has lubricatingcharacteristics, and prior workers have 25 sought to keep some of thewax in the oil by so modifying the pour point of the oil that in spiteof its wax content the oil can be used for lubricating at lowtemperatures. This has been accomplished in recent years by adding tothe 30 oil substances to which the name pour point depressors has beengiven. Quite a few substances for this purpose have been discovered.Theoretically it is assumed that a pour point depressor inhibitscrystallization of the paraflin 35 wax in the oil and thus prevents theoil, when subjected to low temperatures, from forming a. kind of sludgeor slush of relatively large wax crystals occupying the entire volume ofthe oil and occluding liquid oil within the network of 40 crystals.

At the present time condensation products between chlorinated paraflinsand aromatics are used to a considerable extent as pour pointdepressors. Products of this nature are much less effective in theiractions than compounds described in this invention. In addition theycontribute nothing to the oiliness of the-lubricant to which they areadded, which is markedly different from our products.

In all instances the amount of pour point depressor added is relativelysmall. The quantities generally average a fraction of a percent based onthe quantity of oil.

We have now discovered a class of materials which function particularlywell as pour poin depressors, and which have the added advantage thatthey impart oiliness to the oil. The substances which we use can begenerically defined as acylated coumarones wherein the acyl groupcontains at least twelve carbon atoms. -These acylated coumarones arenew materials in themselves and are the subject matter of the Ralston,Vander Wal and Segebrecht application Serial No. 228, 261, filedSeptember 2, 1938. These compounds are prepared, broadly speaking, byreacting coumarone, or one of its polymers, with a fatty acid chloridehaving at least twelve carbon atoms in the presence of an acylatingcatalyst, such as aluminum-chloride. This reactionresults in theformation of an intermediate complex containing the catalyst which isthereafter hydrolyzed to free it of catalyst, and the final productrecovered. Thus the preparation of these acylated coumarones followsclosely the acylation of other aromatic hydrocarbons by the Friedel-Crafts synthesis. But during the acylation of the coumarone thecoumarone polymerizes. Or it is possible that the coumarone is firstacylated and thereafter the acyl derivative polymerizes. In any event,the final product is an acylated and polymerized coumarone. Or, to putit more definitely, it is a polymerized coumarone containing acyl groupshaving twelve or more carbon atoms. v

In the preparation of these pour point depressors any fatty acidchloride having twelve or more carbon atoms can be used. These can beeither saturated or unsaturated, or they can be fatty acid chloridesmade from fatty acids prepared by the oxidation of paraffin wax or otherhydrocarbons yielding fatty acids on oxidation. Mixtures of two or moredifferent fatty acid chlorides can be used as the ac'ylating agent. Thisgives us final products of mixed character and very complexconstitution. 'Indeed the pour point depressor effect of our productsmay possibly be due to the complex nature of them. As fatty acidchlorides we can use lauryl, myristyl, palmityl, stearyl, oleyl,linoleyl and linolenyl chlorides, these being the more usual ones.

In broad aspects, the fatty acid chloride is added to a suspension ofthe acylating catalyst, such as aluminum chloride, in an inert solvent,and to this mixture coumarone dissolved in an inert solvent is added.The proportions of fatty acid chloride to coumarone canvary over widelimits as wehave found by experiment. This probably means that so longas the coumarone polymer contains at least one acyl group the producthas pour point depressor characteristics.

But more than one acyl group can be present in the final product.

We shall now give an example of how our pour 4 point depressors are madefrom fatty acid chlorides of at least twelve carbon atoms andcoumarones.

Eaample ture is then maintained at 45 C. to 50 C. for V The reactionmixture comprisabout ,one hour. ing an aluminum chloride complex is thendecomposed on ice and the solvents removed by steam distillation. Theproduct is dissolved in ether and the ether solution dried withanhydrous sodium sulfate. The ether is then removed by distillationunder a vacuum.

In precisely the same manner other acylated coumarones are prepared asmore fully disclosed in the aforesaid .application.

The final product is semi-solid and plastic, and resinous in character.It dissolves readily in mineral oils in proportions used for pour pointdepressing.

We shall now indicate by way of example how our products function whenadded to lubricating oils.

In the following examples the oils designated as 1, 2 and 3 are threedifferent kinds of lubricating oils in common commercial use. Theexamples also indicate the pour point of the original oil and the pourpoint of the oil after the addition of our pour point depressors.

Example 1 I saybolt Pour point, F. 011 viscosity at Original TreatedExample 2 0.5% of a product prepared from 12 parts of coumarone and 30parts of oleyl chloride is added giving the following results:

Pour point, F.

Oil

Original Treated Example 3 0.5% of a product prepared from 20 partscoumarone and 30 parts .of stearyl chloride is added to the oils withthe following results:

aybolt P 0111' P nt. F. Oil viscosity at 100 al Treated Second Example 40.5% of a product prepared from 30 parts of coumarone and 20 parts ofstearyl chloride is added to the oils with the following results:

saybolt Pour point, F. Oil viscosity F Original Treated Example 5 0.5%of a product prepared from 30 parts of coumarone and 30 parts of stearylchloride is added to the oils with the following results:

0.5% of a product prepared from 11.8 parts of coumarone and 30 parts oflinolenyl chlorideis added tothe oils with the following results:

'saybo Pout point, F. Oil viscogltyat Original Treated Seconds I Thusfrom the above examples it is apparent that our pour point depressorsaremarkedlyefi'ective for the purpose intended, a pour point lowering ofas much as 50 F. being obtained. Our pour point depressors areespecially effective on oils having rather high pour points, thusindicating the marked ability of our compounds to preventcrystallization of the wax.

Similar results are obtained when other fatty acid chlorides havingtwelve or more carbon atoms are used. The amount of pour point depressorcan vary over wide limits. Noticeable improvement in pour point loweringis obtained when only 0.1% of our products is added. Larger amounts, upto 2% or 3% can also be added but much greater amounts, such as 10% or15% are not necessary in order to obtain a. substantial pour pointlowering.

In addition 'to the property of lowering the pour point of the mineraloils these products also decrease the heat generated during runningfriction. The oils were tested in an apparatus described by Ralston,Hoffman and Stephens, found in National Petroleum News, dated November3, 1937. The following table shows the temperature rises after one hourfor various treated and untreated oils. In the case of the treated oils0.5% of the product described and used in Example 1 is added.

0.5% of the product lowered the pour point of the gas oil from 65F. toF.

In the appended claims we use the language a coumarone" to include thecoumarone dimers, trimers or tetramers as well as coumarone itself sincethe coumarone thereof is the essential polymerizing component.

Although we have referred more particularly to the use of our acylatedcoumarone materials with lubricating oils it is apparent that they canalso be added to lubricating greases where it is desirable to reduce theheat of friction or to prevent the grease Irom assuming a relativelyhard, non-flowing state when subjected to a cold environment. Whenpreparing such greases we can first dissolve the pour point depressor inthe lubricating oil and then make a lubricating grease therefrom in theusual way.

Having thus described our invention, what we claim is:

1. A mineral oil containing, as a pour point depressor, an acylatedcoumarone, the acyl group having at least twelve carbon atoms.

2. A mineral oil contain g. as, a pour point depressor, a stearylatedcoumarone.

3. A mineral oil containing, as a pour point depressor, an acylatedcoumarone polymer wherein the acyl group contains at least twelve carbonatoms.

4. A mineral oil containing, as a pour point depressor, a stearylatedcoumarone polymer.

5. A mineral oil containing, as a pour point depressor, the productobtained by reacting coumarone with a fatty acid chloride having atleast twelve carbon atoms in the presence of an acylating catalyst, andrecovering a catalyst-free product.

6. A mineral oil containing, as a pour point depressor, the product ofreacting a coumarone with stearyl chloride in the presence of anacylating catalyst and recovering a catalyst-free product.

7. The process of depressing the pour point of a mineral oil whichcomprises adding to the oil the products resulting from reacting a.coumarone with a fatty acid chloride having at least twelve carbon atomsin the presence of an acylating catalyst and recovering a catalyst-freeproduct.

ANDERSON W. RALSTON. EVERETT J. HOFFMAN.

